Detonator



July 17, 1923. 1,462,074

w. o. SNELLING DETONATOR Filed June 14 1919 Patented July 17, 1923.

UNITED STATES PATENT OFFICE.

WALTER O. SNELLING, 9F ALLENTOWN, PENNSYLVANIA, ASSIGNOB TO TROJAN POW- DEB COMPANY, OF NEW YORK, N. Y., A. CORPORATION OF NEW YORK.

DE'I'ONATOB.

Application filed June 14, 1919. Serial No. 304,215.

To all whom it may concern:

Be it known that I, WALTER O. SNELLING, a citizen of the United States, and resident of Allentown, Lehigh County, Pennsyl- 6 Vania, have invented certain Improvements in Detonators, of which the following is a specification.

My invention relates to improvements in initial detonating' agents, and refers more I particularly to the preparation of detonating caps and electric detonators having a nitrostarch explosive base.

Hitherto, the employment of nitrostarch as the explosive base in detonators and the like has been unsuccessful, owing to the fact thatthe nitrostarch, when completely confined in a detonating capsule, rapidly undergoes decomposition, the first traces of decomposition products acting as catalysts,

and rapidly bringing about decomposition of the remaining material. Such detonators have been incapable of withstanding storage conditions, and actual tests have shown that a temperature of 100 degrees C. for from five to eight hours is usually sufiicient to bring about explosion.

I have discovered that detonating caps and electric detonators can be made from nitrostarch, and be ca able of meeting successfully the most stringent storage conditions,

and these detonators have actually withstood temperatures higher than the average temperature prevailing in magazines, even in the tropics, for many months without diminution in strength or alteration in stability. To roduce this result I employ nitrostarch whlch is free from decomposable lower nitric acid esters of starch, a method of preparing such nitrostarch being fully set forth and described in my copending application Serial No. 268,498, filed December 27th, 1918, and to secure more satisfactory brisance and stability, I may admix with such nitrostarch a suitable oxidizing as agent, such as potassium chlorate or .am-

monium perchlorate, and a stabilizing agent such as diphenylamine, urea, or dicyandiamid. This nitrostarch I employ as my detonator base, and in connection therewith I prefer to use a primingcharge of a suitable primary detonating agent such as mercury fulminate, lead azid, or the like.

As illustrating a detonator made in ac-.

cordance with my invention, I may employ a detonator cap of the type illustrated in the accompanying drawings, in which:

F igure 1 1s a vertical section of a dot onator cap made in accordance with my inventlon; and Figure 2 is anenlarged perspective of the inner capsule.

lVith reference to the drawings, the cap comprises an outer shell or capsule, 1, closed at one end, which receives the base or main charge, and an inner capsule, 2, dis osed within the outer capsule, 1, and containing a suitable priming charge, both inner and outer capsules being made of co per, nickel, or other suitable material. he base or main charge comprises my nitrostarch free from decomposable lower nitric esters of starch, mixed with suitable proportions of an ox dizing agent and a stabilizing agent if desired, and the priming charge preferably comprises mercury fulminate, lead azid, or other primary detonatin agent. To make a detonator cap having the same strength as a detonating ca of mercury fulmlnate of what is called o. 6 grade, and corresponding to a charge of one gram of mercury fulminate, I prefer to employ an outer capsule of copper, 5.60 mm. in inside diameter, and 38 mm. in length. As anlnner capsule I prefer to employ a capsule 5.50 mm. in outside diameter and 9 mm. in length. As my priming charge I may employ .4 g. of a mixture of parts of mercury fulminate and 20 parts of potasslum chlorate, and as my main charge I may employ .5 g. of a mixture consisting of 80% of nitrostarch of a proximately 13% nitrogen, and free from d composable lower nitric acid esters of'starch, 15% of ammonium Iperchlorate, and 5% of diphenylamine. press the charge as indicated into my detonating capsule under a pressure of kg., and under these circumstances I obtain detonating caps which are both stable and satisfactorg, will withstand a temperature of for several months without exploding, and which will withstand a temperature higher than the average temperature prevailing in magazines, even in the tropics, for many months with neither diminution in strength nor alteration in stability.

I have found that the best results are obtained when from 70% to 90% of nitrostareh is used with from 10% to 25% of potassium chlorate or animoninm perchlorate and 1% to 10% of diphenylamine, urea, or dicyandiamid, but I do not "Wish to be limited to any specific proportions in which the various elements of the explosives may be mixed, since it is obvious that wide latitude in this respect is allowable with minor changes in the strength and explosive character of the detonator only, and With no departure from the essential features of the invention. Nor do I Wish to be limited to the particular method of preparing nitrostarch free from decomposable lower nitric acid esters of starch herein mentioned, since I have discovered that nitrostarch made by any process, if free from decomposable lower nitric acid esters of starch, is suitable for use in making stable and satisfactory detonators.

I claim:

1. A detonator comprising an initial priming charge and a main charge comprising nitrostarch.

2. A detonator comprising an initial priming charge comprising mercury fulminate, and a main charge comprising nitrostarch.

3. A detonator comprising an initial priming charge, and a main charge comprising nitrostarch and an oxidizing agent.

4. A detonator comprising an initial priming charge, and a main charge comprising nitrostarch and potassium chlorate.

5. A detonator comprising an initial prinn ing charge, and a main charge comprising nitrostarch, an oxidizing agent, and a stabilizing agent.

6. A detonator comprising an initial prim ing charge, and a main charge comprising nitro-starch, potassium chlorate, and diphenylami-ne.

WALTER o. SNELLING. 

